Opening- and closing safety-valves of steam-boilers



UNITED STATES PATENT OFFICE.

SAMUEL RAIIB, ,IR, OF \VILKES-BARRE, PENNSYLVANIA.

OPENING AND CLOSING SAFETY-VALVES OF STEAM-BOILERS.

Specification of Letters Patent No. 75, dated November 8, 1836.

To all whom it may concern:

Be it known that I, SAMUEL RAUB, J r., of VVilkesBarre, in the county ofLuzerne and State of Pennsylvania, have invented an Improvement in theMode of Opening and Closing the Safety-Valves of Steam-Boilers, whichimprovement renders the valve selfacting whenever the water in theboiler descends below the proper water-line; and I do hereby declarethat the following is a full and exact description thereof.

I in general construct my safety valve in the ordinary way, using thecommon conical valve, and seat, and a lever of second kind with itsmovable weight, and my improvement in extending the lever beyond thefulcrum on the side opposite to that upon which the weight is hung sothat it becomes like a scale beam with unequal arms, and receives acounterweight suspended to it by a suitable rod passing through astuffing box in the top of the boiler, the counter weight beingordinarily submerged in the water contained in the boiler.

It is a well known principle in mechanical philisophy that a bodysubmersed in water loses as much of its effective weight as is equal tothe actual weight which it displaces, if therefore there be suspended tothe short arm of the lever above described a weight which in air is anexact counterpoise to the weight, by which the valve is loaded on thelong arm, the whole pressure would be taken off the valve, but onsubmersing such counterpoise in water, the Valve would be forced downwith a power dependent upon the weight of water thereby displaced. Suchis the action of my weight within the boiler. When the boiler issufficiently full of water the weight may be wholly submersed, and theupward pressure of the water will be added to that of the weight bywhich the valve is loaded be the same more, or less, but when the watersinks below the weight within the boiler its tendency is then tocooperate with the elasticity'of the steam and to open the valve,which-tendency increases as the water be-v comes exhausted, and wouldcontinue to increase until the weight was entirely uncovered by water,did not the opening of'the valve previously take place.

It is manifest that by this contrivance the two weights may be soadjusted to each other as that the valve may be made to open under anyrequired degree of pressure, and that this opening may take place by theclasticity of the steam alone, without the water being too muchexhausted as in the ordinary construction, but that when such exhaustiontakes place the gravity of the interior weight operates concurrentlywith the elasticity of the steam. It is also manifest that the operationof the interior weight as described is not the same with those floatswhich have been applied in different ways either to. let off a portionof steam, or act as a tell talc when the water subsides, or to set inoperation a feeding apparatus, but that the only, and direct effectwhich I wish to produce is the actual opening ofthe safety valve, andthe blowing off of the steam.

The kind of weight which I use will depend upon the construction of theboiler in which it is employed, as for example in boilers the fines ofwhich are but a few inches under water, the weight must be in such ashape as will be adapted thereto. It will be best made of metal, and itmay be either solid, or hollow so that its weight, and bulk may bear anydesired proportion to each other.

I have thus described what I deem the best arrangement for carrying theprinciple upon which I proceed into effect, but other arrangements maybe resorted to, by which the same end may be attained. There may, forexample, be added 011 the side of the fulcrum opposite to the ordinaryvalve, a second valve opening inward, and exposing an equal area to theaction of the steam, in this case, the pressure of the steam being equalupon both valves they will remain stationary under th elastic pressureof the steam alone, but when the inside weight is not sustained by thepressure of the water, both valves will be opened, and the steam willescape through the double outlet. With the addition of this reversedvalve the outside weight maybe much diminished, or it may be entirelyomitted, the closing of the valve being effected by the pressure of thesteam on the reversed valve.

I claim as my inventionsteam, thereby preventing all danger of ex- Theapplication of a Weight Within the plosion from the undue exhaustion ofthe boiler of a steam engin which as the boiler Water.

becomes exhausted shall operate upon the SAMUEL RAUB, JR. 5 principle,and in the manner herein set Witnesses:

forth, so as to open the safety valve, or T'Hos. P. JONES,

valves, and thus cause the free escape of JACOB BUTH.

